Cloned (Comment) | Organism |
---|---|
expression of the beta-subunit and a modified form of the alpha-subunit with a single cysteine replacement in the TM5/TM6 extracellular loop, i.e. S806C, in Xenopus laevis oocytes | Rattus norvegicus |
Protein Variants | Comment | Organism |
---|---|---|
E820A | site-directed mutagenesis, shows altered pH dependence compared to the wild-type enzyme | Rattus norvegicus |
E820D | site-directed mutagenesis, charge-conserving mutation, slight preference of the mutants for the E2P state, shows no altered pH dependence compared to the wild-type enzyme | Rattus norvegicus |
E820K | site-directed mutagenesis, charge-inverting mutation, no shift in the conformational distribution toward E1P | Rattus norvegicus |
E820Q | site-directed mutagenesis, shows altered pH dependence compared to the wild-type enzyme | Rattus norvegicus |
K791A | site-directed mutagenesis, charge-neutralizing amino acid replacement, insertion of the Lys791 mutations into the backbone of H,KATPase mutant S806C, which carries a reporter cysteine for site-specific fluorescence labeling. The mutation causes a conformational shift toward the E1P-state and a shift to more positive potentials compared with the wild-type | Rattus norvegicus |
K791E | site-directed mutagenesis, charge-inverting mutation, insertion of the Lys791 mutations into the backbone of H,KATPase mutant S806C, which carries a reporter cysteine for site-specific fluorescence labeling. The mutation causes a conformational shift toward the E1P-state and a shift to more positive potentials compared with the wild-type | Rattus norvegicus |
K791R | site-directed mutagenesis, charge-inverting mutation, insertion of the Lys791 mutations into the backbone of H,KATPase mutant S806C, which carries a reporter cysteine for site-specific fluorescence labeling. The mutation causes a conformational shift toward the E1P-state and a shift to more positive potentials compared with the wild-type | Rattus norvegicus |
K791S | site-directed mutagenesis, charge-neutralizing amino acid replacement, insertion of the Lys791 mutations into the backbone of H,KATPase mutant S806C, which carries a reporter cysteine for site-specific fluorescence labeling. The mutation causes a conformational shift toward the E1P-state and a shift to more positive potentials compared with the wild-type | Rattus norvegicus |
additional information | inversion of the salt bridge polarity does not rescue function does not necessarily exclude that Lys791 and Glu820 in the wild-type proton pump interact in an E2P-stabilizing manner | Rattus norvegicus |
S806C | a single cysteine replacement in the TM5/TM6 extracellular loop of the alpha-subunit. The S806C mutation enables site-specific labeling of H,K-ATPase with the environmentally sensitive fluorophore TMRM, the S806C mutation does not affect the transport properties of gastric H,K-ATPase | Rattus norvegicus |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
SCH28080 | a K+-competitive inhibitor, SCH28080 is specific for both E2 and E2P conformations | Rattus norvegicus | |
vanadate | interacts specifically with the E2 conformational state | Rattus norvegicus |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
plasma membrane | transmembrane enzyme | Rattus norvegicus | 5886 | - |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + H2O + H+/in + K+/out | Rattus norvegicus | - |
ADP + phosphate + H+/out + K+/in | - |
ir |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Rattus norvegicus | P09626 | - |
- |
Posttranslational Modification | Comment | Organism |
---|---|---|
phosphoprotein | reversible phosphorylation of a highly conserved Asp residue, a hallmark of all P-type ATPases, is coupled to the transition between two principal conformational states and the corresponding phosphointermediates | Rattus norvegicus |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
gastrointestinal tract | - |
Rattus norvegicus | - |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + H2O + H+/in + K+/out | - |
Rattus norvegicus | ADP + phosphate + H+/out + K+/in | - |
ir | |
ATP + H2O + H+/in + K+/out | cation binding sites in the transmembrane domains TM42 to TM6, E2-conformation-specific salt bridge between the side chains of Lys791 in TM5 and Glu820 in TM6 of the cation binding pocket | Rattus norvegicus | ADP + phosphate + H+/out + K+/in | - |
ir | |
additional information | activity tests of the recombinantly expressed enzyme by Rb+ uptake measurements, and voltage clamp fluorometry for site-specific labeling of H,KATPase-expressing TMRM-labeled oocytes | Rattus norvegicus | ? | - |
? |
Subunits | Comment | Organism |
---|---|---|
More | homology model of the gastric H,K-ATPase in the E2 state | Rattus norvegicus |
Synonyms | Comment | Organism |
---|---|---|
H+/K+-ATPase | - |
Rattus norvegicus |
H,K-ATPase | - |
Rattus norvegicus |
General Information | Comment | Organism |
---|---|---|
evolution | the ubiquitous Na,K-ATPase and the gastric H,K-ATPase belong to the PIIC subgroup of the extensive class of P-type ATPases, which use ATP hydrolysis for active transport of cations. A lysine residue within the highly conserved center of the fifth transmembrane segment in PIIC-type ATPase alpha-subunits is uniquely found in H,K-ATPases instead of a serine in all Na,K-ATPase, EC 3.6.3.9, isoforms | Rattus norvegicus |